Violence has marked the fourth anniversary of the US-led war on Iraq which has claimed tens of thousands of lives.
Today, 16 people, including two US soldiers were among those killed in car bomb and mortar attacks, across Baghdad.
In the country's western Anbar province, tribal fighters and police clashed with al-Qaeda linked militants near Fallujah.
A provincial official in Ramadi said 39 militants were killed, along with nine tribal fighters and eight policemen.
The latest violence comes as a US general said Iraqi insurgents used children in a suicide attack at the weekend, raising worries that the insurgency has adopted a new tactic to get through security checkpoints with bombs.
An average of 100 people a day have been killed in Iraq since Saddam Hussein was ousted from power in March 2003.
Humanitarian impact of war highlighted
The UN Refugee Agency has said there has been an abject denial around the world of the humanitarian impact of invading Iraq.
The UNHCR said the UN faced an enormous task in helping Jordan and Syria cope with a huge influx of Iraqi refugees.
Some two million Iraqis are now in neighbouring countries - many of them since before Saddam Hussein was toppled, according to the UNHCR. Another 1.9 million are estimated to be displaced within the country.
About 730,000 Iraqis have fled their homes since the beginning of 2006 and are facing increasing hardship inside Iraq.
The UNHCR estimates that up to 50,000 people are fleeing their homes every month.
An estimated four million people in Iraq are dependent on food assistance, while the rate of chronic malnutrition among children is 23%.
Former Iraqi vice president executed
Saddam Hussein's former vice president, Taha Yassin Ramadan, was executed early today.
He is the fourth person to be hanged for the killing of 148 Shias from the town of Dujail.
Ramadan was given a life sentence in November but an appeal court ruled that he be executed.
The trial court found Ramadan guilty of issuing orders for the systematic detention, torture and killing of men, women and children from Dujail after an attempt on Saddam Hussein's life in the town in 1982.
